One of the nice features of Java language is that it provides you the opportunity to execute native system commands and in this tutorial we will see how to use Runtime class in a quite simple program to execute commands like ipconfig
As an example consider the below snippet
package com.javaonly.system; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class SystemCommandsTest { public static void main(String args[]) { StringBuffer output = new StringBuffer(); try { Process process = Runtime.getRuntime().exec( "ipconfig"); BufferedReader reader = new BufferedReader(new InputStreamReader( process.getInputStream())); String line = ""; while ((line = reader.readLine()) != null) { output.append(line + "\n"); } System.out.println("OUTPUT:"+output.toString()); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }
As you can see in the above class we first need to access the runtime environment.This is done with
Runtime.getRuntime()
method.We also need to create an OS process in order to execute the system command. As you can see this process is created with
exec()
method of the Runtime class.Finally we need to create a BufferedReader in order to read the input stream of the process and display the output in our console.
Executing ipconfig command will give us the below output
OUTPUT: Windows IP Configuration Ethernet adapter Local Area Connection 2: Connection-specific DNS Suffix . : IP Address. . . . . . . . . . . . : 192.168.2.3 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.2.1
ref：http://www.java-only.com/LoadTutorial.javaonly?id=117